The studies will be concerned with those mutations in Neurospora crassa that can alter the morphology and growth patterns of this organism. Experimentally induced aberrations in Neurospora have produced measurable changes in cell permeability, cell walls, growth rates and growth patterns. These pleiotropic effects are often associated with large changes in the lipid composition of the mold. The proposed studies should provide further insight into the apparent effects of aberrations concerning the biosynthesis of lipids on the morphology of Neurospora. The control mechanisms involved in fatty acid synthesis will be studied in detail. The emphasis in this phase of the work will be put on those enzymes that are implicated in the turnover of NADPH and NADH.